Last weekend our system A photocell missed the finish of the 2nd competitor and registered a false finish 20 seconds later (the only one of the day). It picked up the 3rd competitor who was already on course. Checked the beams - needles pegged in the green, fresh batteries and tested OK. Missed the 3rd & 4th finishes then worked fine for the rest of the day. We were running on a 50' long DIN cable, and using the RLS1n and 1nd combination. Later in the race, we lost communication on that same cable. Replaced amp and headset with units known to be working but could not resume coms. Could this be a bad cable? Any other ideas?

Make sure that the photocell beams are discrete. Move to the center of the trail and bring your hand up from the snow until it triggers the primary. Then bring your other hand down from the top until it triggers the backup. You want both beams to be about 8 inches apart at the center of the trail. I suspect that you have the cells set too close together and they are bleeding into each other.

The new PR1a photocells

http://www.phoenix-sports.com/alge_pr1a.htm

Have the SYNC cable to create an alternating sequence of pulses to avoid issues with beam bleed.

Thanks for the reply. Will check for beam bleed on next setup. Cleaned all connections & checked cable for continuity - it was good.

This sounds like a strange problem and you may have to look beyond the eyes for the solution.

Some silly questions:

What was the timer the you were using?

Did it show up on time at the timer and not the computer (assuming you are using one)

I was also try a different cable and was it above freezing and was the cable lying in any water.

Or was the cable running parallel to something like a power cable that had a lot of current running in it?

This is going to be a little harder to figure out. The RLS1's have no real way of 'storing' a pulse.

Mike

We were using an S4. False finishes showed up on both, missed finishes were missed on both. Cable was mostly elevated but might have contacted the snow. Snow was not particularly wet. Temperature was about 30F with high winds. Cable might have been running parallel to a power cable for a couple feet. Cable was powering computers & clocks. Cable continuity has tested OK even with movement. Used this systam last weekend with a different cable and it worked fine. Using again in two weeks with the cable we used when this happened.